Borealis

Borealis

Character builder for fifth edition

Build, level up and print your tabletop heroes. Free and open source, on your desktop and your phone, and everything stays on your device.

Download Borealis All platforms

Version 2.0.0 · MIT or Apache-2.0 · No account, no ads, no telemetry

The thirty-second tourFrom a blank page to a printed hero

Real screen recordings of Borealis on macOS: creating a level 1 wizard, picking spells, previewing the sheet, importing a homebrew pack and asking the optional AI a rules question. Has sound.

What it doesEverything a character needs, nothing it doesn't

Create and level up, step by step

Species or race, class, background, ability scores, languages, proficiencies, feats and gear, in the order you would do it at the table. Roll your scores (3d6 or 4d6 drop lowest), use point buy or the standard array. Level up from 1 to 20, multiclass, and let Borealis keep the arithmetic straight.

 

Borealis on macOS, Build tab, Ability Scores: six scores set with point buy (13, 12, 14, 17, 11, 8) and their modifiers, with a description of each ability on the right.
Ability scores with point buy, on macOS.

Spells, slots and spellbooks

Pick cantrips and spells for every caster, keep a wizard's spellbook, prepare the day's list and read every spell in full. Slots follow your levels, including multiclass casters.

The Magic tab: a level 1 wizard's spell list with cantrips and level 1 spells, Shield selected and its full description shown on the right.
Preparing spells. Shield is selected; its full text is on the right.

A character sheet worth printing

Generate a clean PDF of your character: stats, skills, attacks, features, spell pages and cards. Colour or ink-saving, fillable or flattened, Letter or A4. Print it, or fill it in on a tablet.

A Borealis spellcasting page for a level 5 wizard: class, ability, save DC and attack bonus, with cantrips and slots by level. The first page of a Borealis character sheet for Seraphine Vale, an elf wizard: ability scores with saves and skills, armour class, hit points, attacks, senses, proficiencies and conditions.

Bring the content you already have

Borealis imports Aurora Builder XML content and .dnd5e character files, shows you a preview of what will be added, and installs it. It can also read your own local 5etools data folder. All of it is plain, offline parsing: no AI involved.

Import content you own or are licensed to use. Only the SRD rules ship with the app.

Importing a homebrew XML file by dragging it onto Borealis: the import preview says two elements from one file will be added, with Install and Cancel buttons. The compendium after the import, showing the homebrew spell Lantern of Last Light next to SRD entries.
Drop a file, check the preview, install. The homebrew spell is in the compendium a moment later.

Bring your own AI, if you want one

Off by default, and nothing needs it. Turn it on and Borealis uses the Claude or Codex command-line tool you already have, with your own account. Ask a rules question and get an answer with links to the rules text you have installed. Turn a homebrew PDF or a photo of a page into a pack you can review and import.

AI features run on desktop. Borealis never sees your account details, and no AI service is built in.

The AI assistant answering how grappling works under the 2024 rules, with inline links and source chips for Grappling, Grappled and the Grappler feat.
A rules answer with its sources. Every claim links to the text it came from.

The same app in your pocket

Borealis runs on iPhone and Android as well as macOS, Windows and Linux. Bring your character to the table and track hit points, resources, rests and conditions during play.

Borealis on iPhone, Play tab: armour class 11, initiative +1, speed 30 feet, 40 maximum hit points, resources with short and long rest buttons, and conditions. Borealis on Android, Build tab: the species step with Elf, High Elf lineage and Intelligence as the spellcasting ability, and the Elf traits below.

Two editions, one appPlay 2014 or 2024 rules

Both rule sets ship in the box, from the free System Reference Documents. You choose the edition for each character when you create it, and that character follows it all the way to level 20.

2014

SRD 5.1

  • Races and subraces, with their ability score bonuses
  • Backgrounds for proficiencies, languages and gear
  • The original classes, subclasses and spell lists

2024

SRD 5.2.1

  • Species, with traits instead of fixed bonuses
  • Backgrounds that raise ability scores and grant an origin feat
  • The revised classes, weapon mastery and updated spells

Imported content can target either edition. The compendium filters by rule set, so you only see what fits.

Yours, and only yoursEverything stays on your device

  • No account

    No sign-up, no cloud save, no ads. Your characters are files on your device that you can copy, back up and share.

  • No telemetry

    Borealis does not phone home. It goes online only when you ask it to, for example to download content from an index file you added.

  • AI only if you say so

    Optional, off by default, and run through your own command-line tool and account. Turn it off and nothing changes.

Free, foreverDownload Borealis 2.0.0

Pick your platform. Every download comes from the project's GitHub releases.

Open the releases page

All releases and checksums · Source code

First launch: the builds are not code-signed yet

Signing certificates cost money that a free project does not have yet, so your system will warn you once. The source is public if you would rather build it yourself.

macOS

  1. Open the .dmg and drag Borealis to Applications.
  2. Right-click Borealis and choose Open, then Open again.
  3. On macOS 15 or later, if that is not offered: open System Settings, Privacy & Security, and click Open Anyway.

Windows

  1. Run the installer. If SmartScreen says "Windows protected your PC", click More info.
  2. Click Run anyway. It installs for your user only, no admin prompt.

Linux

  1. AppImage: chmod +x Borealis_*.AppImage, then run it.
  2. Or install the .deb or .rpm with your package manager.

Questions at the tableFAQ

Is it really free?

Yes. Borealis is open source under MIT or Apache-2.0, at your option. There is no paid tier, no subscription and no ads, and the licence means it stays that way: anyone can build it from the source.

Does it work offline?

Yes. The rules, your characters and the sheet generator are all on your device. It only goes online when you ask it to, for example to download content from an index file or to use the optional AI through your own tool.

Does it run on phones?

Yes, on iPhone and Android, with the same characters and content as the desktop. Android builds can be installed from the releases page; iPhone needs the App Store listing, which is not live yet. AI features are desktop only.

Can I import my Aurora content?

Borealis imports Aurora Builder XML content files and .dnd5e character files without any AI: you see a preview of what will be added before you install it. Import content you own or are licensed to use.

Can I use my 5etools data?

Yes. Point Borealis at your own local 5etools data folder and pick the sources to import. The result stays on your device and is never shared or uploaded. As with any import, use data you own or are licensed to use.

Which rules are included?

The System Reference Documents 5.1 (2014) and 5.2.1 (2024), both under the Creative Commons Attribution 4.0 licence. Anything beyond the SRD comes from content you import.

Do I need an AI subscription?

No. Every feature except the AI assistant works without one, and the assistant is off until you turn it on. If you do, it uses the Claude or Codex command-line tool you have installed, with your own account.

Why does my computer warn me when I open it?

The builds are not code-signed yet. See First launch above for the one-time steps on macOS and Windows.